07576 573615tom@cbsdamp.co.uk Mon–Fri 8am–8pm · Sat 8am–1pm · Sun closed About Services Areas Our work Contact 07576 573615Request Free Survey HomeAreas coveredIsleworth Damp proofing in Isleworth # Damp proofingin Isleworthfor riverside and period homes Old Isleworth's riverside cottages, Georgian and Victorian terraces, interwar semis and the streets bordering Osterley and St Margarets each bring their own damp problems. Free diagnosis, a written fixed price, and ten-year guarantees on damp treatment. Request your free survey 07576 573615 Free survey across Isleworth · Sovereign & Wykamol approved contractor · 10-year QANW insurance-backed guarantee 10 years Company workmanship guarantee on damp treatment 10 years QANW insurance-backed guarantee £0 Survey, diagnosis and fixed-price quotation in Isleworth £2m Public liability insurance held Local coverage ## Isleworth's mixed housing stock needs a careful diagnosis Old Isleworth keeps a knot of narrow streets around Church Street and Lower Square where Georgian and early Victorian cottages sit close to the Thames, many with solid brick walls and no cavity, and some converted from older buildings with uneven floor levels and thick masonry. This riverside quarter sits on ground that stays damp for much of the year, and a handful of properties are close enough to the water to face occasional flood risk. Further back from the river, Isleworth spreads into the more conventional Victorian terraces around Spring Grove and the interwar semi-detached and terraced housing that fills much of the area towards Osterley, built with cavity walls in the 1920s and 1930s in a style consistent with much of Middlesex. Streets on the St Margarets fringe share some of the older riverside character while sitting slightly further from the water, and the housing there is a mix of Victorian terraces and later infill, each needing its own assessment rather than a single template. Isleworth's Georgian and early Victorian cottages predate any reliable damp proof course, and their solid walls were built to manage moisture by breathing through lime mortar, a very different approach from the interwar cavity housing found towards Osterley. We survey free of charge across Old Isleworth, the Isleworth riverside, the St Margarets fringe, Osterley, Spring Grove and the surrounding streets, with calls taken Monday to Friday 8am to 8pm and Saturday 8am to 1pm. ### Areas we cover within Isleworth - Old Isleworth - Isleworth Riverside - St Margarets fringe - Osterley - Spring Grove - Lower Square - Church Street - Isleworth Ait ### Property types we work on Georgian and Victorian riverside cottages in Old Isleworth, Victorian terraces around Spring Grove, and interwar cavity semis and terraces towards Osterley and the St Margarets fringe. ### Common Isleworth requests Rising damp in solid-wall riverside cottages, damp linked to a high local water table near the Thames, and bridged cavities or raised ground levels in the interwar semis further out. ### Old Isleworth's older buildings Some of the oldest cottages near Church Street and Lower Square have been altered and extended over centuries, and the survey looks at each wall on its own construction rather than assuming a single build date. ### When you can reach us - Monday8am – 8pm - Tuesday8am – 8pm - Wednesday8am – 8pm - Thursday8am – 8pm - Friday8am – 8pm - Saturday8am – 1pm - SundayClosed Services in Isleworth ## Every service available across Isleworth ### Rising damp treatment A failed damp proof course is diagnosed, treated with an accredited Sovereign or Wykamol system and replastered to a decoration-ready finish, priced as a fixed sum before any work starts, and guaranteed for ten years. Rising damp treatment in Isleworth ### Penetrating damp treatment Damp that worsens after rain is coming in from somewhere. We find the route: pointing, render, sills, gutters or roof detail; correct it, then repair the wall inside. Free survey, fixed price, no guesswork. Penetrating damp treatment in Isleworth ### Damp surveys & diagnosis Find out exactly what is causing the damp, what it takes to fix it, and what it costs, in writing, at a fixed price, with no charge for the visit and no obligation to proceed. Damp surveys & diagnosis in Isleworth ### Structural waterproofing & tanking Below-ground rooms need a waterproofing system, not a coat of damp-seal paint. Membrane and cementitious tanking specified to suit the structure, installed as an approved Sovereign and Wykamol contractor, with a free survey and a fixed price. Structural waterproofing & tanking in Isleworth ### Plastering The replaster is half of any damp repair. We remove contaminated plaster, apply the specified salt-retardant system and leave a flat, decoration-ready finish, as part of a fixed price, by the same contractor that treated the wall. Plastering in Isleworth ### Rendering Cracked, hollow or blown render holds water against your masonry. We identify why it failed, repair or renew it with a system suited to the substrate, and fix the damp it was causing inside. Rendering in Isleworth ### Brickworks & repointing Open joints and spalled brick faces are the most common route for penetrating damp. We cut out properly, repoint in a mortar matched to your brick, and replace masonry that has broken down. Brickworks & repointing in Isleworth ### Brick stitching Helical stainless bars bonded into the bed joints tie cracked brickwork back into one structure, a repair carried out from the outside, without rebuilding the wall, and finished so the crack disappears. Brick stitching in Isleworth ### General building Damp repairs rarely stop at the damp. We carry out the associated building work: masonry, render, plaster, joinery repairs and making good, so the job finishes with one contractor accountable for all of it. General building in Isleworth ### Small refurbishment & remedial works Treatment stops the damp; remedial work makes the room liveable again. Plaster, joinery, floors, decoration preparation and making good, completed by the contractor that did the specialist work, at a fixed price. Small refurbishment & remedial works in Isleworth Why choose us ## Why Isleworth homeowners use Charge Building Services ### We understand riverside and solid-wall cottages Old Isleworth's Georgian and Victorian riverside stock behaves differently from the interwar cavity housing elsewhere in the area, and we diagnose accordingly. ### Experience with mixed housing ages From centuries-old riverside cottages to 1930s cavity semis towards Osterley, the survey is built around what is actually in the wall. ### Two ten-year guarantees A 10-year company workmanship guarantee plus a separate 10-year QANW insurance-backed guarantee on damp treatment. ### Approved Sovereign & Wykamol contractor Accredited products and systems installed to the manufacturer's specification. ### One contractor for damp and fabric repairs Repointing, replastering, brick repair and making good, all handled in-house without subcontracting the finish. ### Free survey and fixed price Free survey, diagnosis and written fixed-price quotation. 50% deposit, 50% on completion by bank transfer. £2,000,000 public liability insurance. Local damp problems ## Why Isleworth properties get damp Isleworth's damp problems split fairly cleanly along construction lines. The Georgian and Victorian riverside cottages of Old Isleworth face rising damp made worse by a high local water table, while the interwar semis towards Osterley show the more familiar cavity-bridging faults found across Middlesex. The streets in between, around Spring Grove and the St Margarets fringe, mix both patterns depending on when each terrace or villa was actually built. ### High water table near the Thames Old Isleworth and the riverside streets sit on ground that stays saturated for long periods, driving moisture up through solid brick and stone foundations regardless of any damp proof course. ### Absent or failed damp proof courses Many of the Georgian and early Victorian cottages in Old Isleworth predate reliable damp proof courses altogether, and any later slate DPC has usually failed after a century or more in the wall. ### Cement pointing and render on soft brick Hard cement repairs on the older cottages and terraces trap moisture that the original lime mortar was designed to release, showing as damp patches and spalling brick faces. ### Occasional flood exposure A small number of properties closest to the river can take in water during exceptional tides, leaving residual salts in the walls that need proper drying out rather than simple redecoration. ### Bridged cavities in interwar semis Towards Osterley and the St Margarets fringe, 1920s and 1930s cavity walls are commonly bridged by mortar debris in the cavity, raised drives and patios, or cracked render letting water through to the inner leaf. ### Altered and extended older buildings Some of the oldest cottages near Church Street and Lower Square have been extended or converted over centuries, and uneven floor levels or hidden solid-to-cavity junctions can mask the real source of a damp problem until surveyed properly. Our process ## The same five steps on every job in Isleworth 01 ### Free survey and diagnosis We inspect the property, identify the actual cause of the damp and explain it in plain terms. No charge, no obligation. 02 ### Fixed-price written quotation A clear fixed price for the specified works, built around your property, never a day rate. 03 ### Works carried out Accredited Sovereign and Wykamol systems installed, walls replastered and the area made good. 50% deposit, 50% on completion by bank transfer. 04 ### Verification and making good Treatment checked for continuity, plaster left flat and decoration-ready, and the area cleaned down. 05 ### Guarantees issued A 10-year company workmanship guarantee plus a 10-year QANW insurance-backed guarantee on damp treatment. In detail ## Damp proofing across Isleworth in detail ### Rising damp in Old Isleworth's riverside cottages A survey in Old Isleworth, particularly around Church Street and Lower Square, often finds tide marks and salt staining consistent with a solid wall drawing moisture from ground that rarely dries out fully because of the proximity to the Thames. Where a genuine DPC failure or absence is confirmed, we inject a chemical damp proof course using an accredited Sovereign or Wykamol system, followed by salt-retardant replastering once contaminated plaster has been stripped back. Because so many of these cottages were built or altered before any reliable damp proof course existed, the survey also checks ground levels against the internal floor, since paths, patios and flower beds raised over the centuries can bridge even a sound wall. ### Lime mortar and cement repairs on older cottages A good deal of the damp reported in Old Isleworth's older buildings is not rising damp at all, but the result of cement pointing or render applied over soft, historic brick that was designed to breathe. Cement traps that moisture instead, and it reappears as damp patches and spalling brick faces inside. Repointing in a lime-based mortar matched to the original, and removing hard cement render where appropriate, restores the wall's ability to manage moisture on its own terms. ### Flood risk and residual moisture near the river A handful of Isleworth properties closest to the Thames, including those near Isleworth Ait, face occasional flood exposure during exceptional tides. A wall that has taken in flood water holds salts and residual moisture that keep coming back after redecoration until identified and treated properly, so flood history is part of the survey, not an afterthought. Drying out a flood-affected wall takes longer than treating ordinary rising damp, and replastering too soon simply traps the moisture behind new plaster. ### Interwar semis towards Osterley Moving away from the river towards Osterley and the St Margarets fringe, the housing shifts to 1920s and 1930s cavity semis and terraces, much closer in construction to the rest of Middlesex. Here the familiar interwar faults appear: mortar bridging the cavity, raised drives and patios bridging the DPC, and cracked render letting water through to the inner leaf. We survey and treat both the older solid-wall cottages and this later cavity housing, and the diagnosis differs accordingly rather than following a single template. ### Mixed terraces around Spring Grove The Victorian terraces around Spring Grove sit between the two patterns, some solid-walled and pre-dating a reliable damp proof course, others built later with an early cavity. Establishing which is which at survey stage avoids treating a wall for a fault it does not actually have. Where these terraces have been converted into flats, we identify clearly whether a defect sits within a single flat's demise or is a shared, external repair, and put that in writing for the freeholder or managing agent. Questions ## Damp proofing in Isleworth, common questions Which parts of Isleworth do you cover?Old Isleworth, the Isleworth riverside, the St Margarets fringe, Osterley, Spring Grove and the surrounding streets. Does being close to the Thames make damp worse in Isleworth?It can. Old Isleworth and the riverside streets sit on ground that stays saturated for long periods, and a small number of properties also face occasional flood exposure, both of which are assessed at survey. My cottage in Old Isleworth is very old, can you still treat it?Yes. Older cottages need lime-compatible repair and a careful check of ground levels rather than a generic chemical DPC alone, and the survey reflects that. Do the interwar semis near Osterley get damp for the same reasons?Not usually. Cavity semis of that period more commonly suffer from bridged cavities, raised ground levels or cracked render, a different diagnosis from the older solid-wall cottages nearer the river. How much does damp proofing cost in Isleworth?It depends on the wall construction, proximity to the river, replastering required and the extent of any repairs. The survey and written fixed-price quotation are free. My house near the river was flooded, can you dry it out?Yes. Flood-affected walls need a period of controlled drying and salt-retardant replastering rather than the standard rising damp treatment, and we assess that at survey. I own a flat in a converted Isleworth terrace, will you deal with the freeholder?We will identify whether the defect is within your flat or a shared external repair and put the diagnosis in writing so you can take it to the freeholder or managing agent. Is my damp likely to be rising damp or something else?In Isleworth it could be a failed or absent DPC, cement pointing trapping moisture, a high local water table, or a bridged cavity in later housing. The survey identifies which before any treatment is proposed. Is your work guaranteed?Damp treatment carries a 10-year company workmanship guarantee plus a separate 10-year QANW insurance-backed guarantee. Building works carry a 6-month workmanship guarantee. Is the survey free?Yes, along with the diagnosis and the written fixed-price quotation, with no obligation to proceed. Free survey ## Free damp survey anywhere in Isleworth Send the postcode and a short description of the problem, including whether the property is near the river or has a cellar, and we will arrange a survey and a written fixed price. - Free survey, diagnosis and written fixed-price quotation in Isleworth - 10-year company workmanship guarantee on damp treatment - 10-year QANW insurance-backed guarantee - Sovereign & Wykamol approved contractor - £2,000,000 public liability insurance Call 07576 573615 Nearby areas ## We also cover ### Damp proofing in Chiswick From the ornate Victorian terraces of Bedford Park to the riverside cottages of Strand-on-the-Green, Chiswick's housing stock sits close to the Thames and its high water table. Free diagnosis, a written fixed price, and ten-year guarantees on damp treatment. View area ### Damp proofing in Ealing Solid-brick Victorian and Edwardian villas, cellars, converted flats and parapet-fronted terraces: Ealing's housing stock rewards a careful survey. Free diagnosis, a written fixed price, and ten-year guarantees on damp treatment. View area ### Damp proofing in Middlesex We are based in Ealing, so Middlesex is home ground. Interwar semis, period terraces and modern extensions, free survey, honest diagnosis, fixed price and ten-year guarantees on damp treatment. View area ### Damp proofing in West London West London's Victorian terraces, Edwardian conversions and interwar semis are the properties we work on most. Free survey and diagnosis, a written fixed price, and ten-year guarantees on damp treatment. View area All areas coveredAll servicesHomeContact Damp proofing, structural waterproofing and remedial building works across London and the surrounding counties. Tom Charge, Owner. ### Contact - 07576 573615 - tom@cbsdamp.co.uk - C/O MG Tax, 166 College Road, Harrow, England HA1 1BH ### Hours - Monday8am – 8pm - Tuesday8am – 8pm - Wednesday8am – 8pm - Thursday8am – 8pm - Friday8am – 8pm - Saturday8am – 1pm - SundayClosed ### Guarantees - 10-year company workmanship guarantee - 10-year QANW insurance-backed guarantee - 6-month guarantee on building work - Sovereign & Wykamol approved contractor - £2,000,000 public liability insuranceAboutServicesAreasOur workContact ### Damp proofing & building services - Rising damp treatment - Penetrating damp treatment - Damp surveys & diagnosis - Structural waterproofing & tanking - Plastering - Rendering - Brickworks & repointing - Brick stitching - General building - Small refurbishment & remedial works ### Areas we cover - Harrow - Pinner - Stanmore - Edgware - Ealing - Chiswick - Isleworth - Chelsea - Middlesex - Brent - London - West London - Watford - Slough - Buckinghamshire - High Wycombe - Surrey © 2026 Charge Building Services Ltd. 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